Greenwich Park: when you might need an injury compensation lawyer

Most people never need to think about impairment percentages. If your injury is serious, you probably will. The scheme's rules divide injuries by type first, threshold or not, and then, for some entitlements, by the degree of lasting impairment. This page explains both in general terms. Your own claim depends on your diagnosis and on the insurer's decisions, which can be reviewed.

Whole person impairment, or WPI, is a percentage that describes how much a lasting injury affects the body as a whole. It isn't a measure of pain, and it isn't a measure of what you've lost. It's a medical assessment made under set guidelines once an injury has stabilised. In a CTP claim, WPI matters mainly for damages: non-economic loss is only available where WPI is more than 10%.

Because so much can turn on a few percentage points, WPI assessments are often contested. Your treating doctors, the insurer's chosen doctor and, if there's a dispute, a medical assessor through the Personal Injury Commission may reach different figures. Keep every report, and get advice before accepting an assessment you think is wrong.

Serious physical injuries often bring a psychological toll: sleeplessness, anxiety, depression or trauma symptoms. These can be part of your claim in their own right. Tell your doctor how you're coping, and ask about psychology if it would help. Whether a psychological injury is threshold or more is a medical and legal question, and the insurer's decision on it can be reviewed.

A serious injury can change more than the next few months of work. It can limit the kind of work you can do for years, or permanently. In a damages claim, that is called loss of future earning capacity, and it can be a significant part of a serious injury claim. It generally needs evidence from your doctors, your work history and sometimes vocational experts.

The definition works by exclusion. An injury is generally threshold if it is soft tissue damage with no nerve damage and no torn tendon, ligament, meniscus or cartilage, whether the tear is complete or not, or if it is a psychological injury the scheme classes as threshold. Injuries outside that description, such as fractures, torn ligaments or brain injuries, are generally more than threshold.

Getting the classification right early helps. If you have symptoms that could point to nerve involvement or a tear, such as numbness, weakness, locking or a joint giving way, describe them to your doctor. Whether tests are needed is a medical decision. If a diagnosis changes, make sure the insurer has the new evidence, because the classification may need to change with it.

Impairment is generally assessed once an injury has stabilised, meaning it's unlikely to change much with further treatment. Assessing too early can understate a serious injury. The insurer may arrange an assessment, your own doctors may give opinions, and if the insurer and you disagree about the degree of impairment, the Personal Injury Commission can carry out a medical assessment.

• Whether the injury has stabilised
• Scans or tests your doctors have ordered
• Whether you disagree with the result, and the deadline to say so

The most persuasive serious injury claims usually have consistent evidence: the same injuries described the same way, from the hospital to the GP to specialists, with no unexplained gaps in treatment. That consistency comes from telling each doctor the full story and following treatment plans. If a report leaves something out, ask the doctor about it rather than letting it pass.

• Hospital admission and discharge records
• Every Certificate of Fitness, in order
• Records of how the injury affects your work
• Any impairment assessment, and your response to it